Thanks to the research of Dr. William F. Friedman, premature infants with a common heart defect have been spared cardiac surgery for decades.

In 1972, four years after being recruited for the UCSD School of Medicine's founding faculty, Dr. Friedman showed that medical therapy could correct a heart defect in which a large blood vessel remains open abnormally after birth.

The defect, known as patent ductus arteriosus, had commonly been treated with surgery. Dr. Friedman's finding changed that, leading to therapeutic advances in the care of thousands of premature babies born each year in the United States.

While at the University of California San Diego, where he became chief of the division of pediatric cardiology, Dr. Friedman also published the first research on two-dimensional echocardiography in the diagnosis and management of congenital heart disease.

Dr. Friedman, who left UCSD to join the UCLA School of Medicine in 1979, died Aug. 25 at his home in Brentwood. He was 69.

The cause of death was interstitial pulmonary fibrosis, UCLA reported.

"Dr. Friedman was a true leader and visionary in the field of pediatric cardiology," said Dr. Gerald S. Levey, vice chancellor of UCLA Medical Sciences and dean of the David Geffen School of Medicine at UCLA.

At UCLA, Dr. Friedman rose to executive chairman of the department of pediatrics, senior adviser to the provost and dean of the School of Medicine. He directed the training program in pediatric cardiology and, in 1997, was named senior associate dean for academic affairs.

Dr. Friedman was born July 24, 1936, in New York City, and earned his bachelor's degree at Columbia University in 1957.

In 1961, he graduated cum laude from State University of New York Downstate Medical Center.

Before joining the UCSD faculty, he served as a senior investigator and pediatric cardiologist at the National Heart Institute in Bethesda, Md.

To treat patent ductus arteriosus, he pioneered the application of a prostaglandin synthesis inhibitor, indomethacin.

Patients with patent ductus arteriosus have a characteristic heart murmur that can be detected by a stethoscope. If left untreated, the disorder can result in heart failure.

In the 1970s, Dr. Friedman's research included the relationship between vitamin D, unexplained excess calcium in the blood and narrowing of the heart's major arterial outlet, the aorta, above the aortic valve.

While based at UCSD, he served as civilian consultant in pediatric cardiology to Camp Pendleton and at what is now the San Diego Naval Medical Center. He also was a consulting pediatric cardiologist at Kaiser Foundation, Children's, Palomar, Alvarado and Grossmont hospitals.

The San Diego County Heart Association designated Dr. Friedman a William Deely Memorial Lecturer.

His career honors included the Cummings Award of the American College of Cardiology, the Distinguished Scientific Achievement Award, and the Award of Merit and the Outstanding Achievement in Cardiovascular Medicine Award from the American Heart Association.

Dr. Friedman was appointed in 1994 by then-Gov. Pete Wilson to the California Medical Board and in 1997 to the California Air Quality Board.

He was the editor of Pediatric Research and associate editor of Pediatric Annals.

Survivors include his wife of 29 years, Denise; sons, Michael and Jonathan Friedman; sister, Vivian Portnoy of Baltimore; and two grandchildren.

Services are scheduled for 2 p.m. tomorrow at Kehillat Israel in Pacific Palisades. A memorial service at UCLA is pending. Donations are suggested to the UCLA Foundation for the William F. Friedman Memorial Fund at the David Geffen School of Medicine at UCLA, 10833 Le Conte Ave, CHS 12-138, Los Angeles, CA 90095-1722.